# 上下文管理器
def add(x, y):
    # with 监视f 相当于C++的智能指针
    with open('test.txt', 'r') as f:
        if x + y == 10:
            print("return")
            return
        else:
            print("666")
        f.close()


add(4, 1)
add(5, 5)
